Driving mechanism



June 24, 1969 E. L. HANsoN 3,451,605

DRIVING MECHANISM Filed March 14, 1967 INVENTOR. 5v5/N577 L. HA N50/v BM Wfw ATTORNEY June 24, 1969 E;I L HANSON 3,451,605 l DR IVI'NG MECHANISM Filed March 14, 1967 sheet 2 of 2 INVENTOR. EVE/Q57 r L, HA N50/v MIM/777.6%

ATTORNEY United States Patent 3,451,605 DRIVING ME'CHANISM Everett L. Hanson, Los Angeles, Calif., assignor to De Luxe Laboratories, Inc., New York, N.Y., a corporation of New York Filed Mar. 14, 1967, Ser. No. 623,101 Int. Cl. G03b 1/24; 136511 17/22; F1611 31/00 U.S. Cl. 226-76 4 Claims ABSTRACT F THE DISCLOSURE A driving mechanism having a fluid drive unit comprising a rotatable housing which is generally in the form of a body of revolution rotatable about its axis, two sets of opposed spaced blades in the housing, one of the sets of blades being fixedly secured to the housing coaxial thereof and rotatable therewith, the other set of blades being journalled coaxially of the one set of blades and radially therewithin, a shaft drivingly connected to said other set of blades, and a liquid such as oil within the housing interacting With the sets of opposed blades to provide a torque transmitting drive therebetween.

BACKGROUND OF THE INVENTION Field of the invention This invention relates to a novel driving mechanism, such mechanism providing a drive which is characterized by its smoothness, its uniformity, and its automatic control of the driving torque which it delivers. The driving mechanism of the invention may be used to advantage in a great variety of applications. Among such uses of the mechanism are the driving of fabric coating or printing machines, the driving of printing presses such as rotogravure machines, the driving sheet handling mechanisms generally, and the driving of various mechanisms, such as slurry pumps, for example, wherein drives of the above indicated type are advantageous. The driving mechanism of the invention is shown and described herein employed in an apparatus for forwarding a web or strip of flexible material; such material is shown and described hereinafter as being a lm strip, although as above indicated, 1t 1s not limited thereto.

Film strips such as motion picture films travel 1n the direction of their lengths while undergoing various treatments such as development, washing, fixing, and drying. During such treatment the film strips run over rollers and sprockets, being guided and pulled thereby as they pass successively through the various treatment units of the apparatus. It is desirable that the film strips be maintained under tension during their travel; in some film processing machines film strips are engaged by driven sprockets and in other such machines the film strips are engaged by rollers having frictional engagement with the film strips.

Description of the prior art In prior film strip processing apparatus the film strip engaging sprockets and rollers have been driven by a driven shaft through the intermediary of a driving roller set, one roller of which is atlixed to and rotates with the driving shaft and the other roller of which frictionally engages the first roller and is directly connected to the film strip guiding and tensioning roller. Such prior means for driving the lm strip driving sprockets and rollers has not been altogether satisfactory because of the jerky and uneven drive which it imposed upon such sprockets and rollers. As a consequence of such uneven drive the speed of the film strip tended to vary, the film strip was unevenly treated in the various units of the system, and in many cases the film strip was mechanically torn.

SUMMARY OF THE INVENTION The invention provides a novel driving mechanism which may be advantageously employed for driving strip or web material forwarding rollers. Such mechanism iS characterized by its smoothness of drive, by its automatic control of the driving torque which it delivers ,by its simplicity, and by its economy of space. Such mechanism occupies little, if any, greater space than prior frictional driving mechanisms, and thus may be readily substituted for frictional driving mechanisms in existing equipment.

The :driving mechanism of the present invention, as above indicated, interposes a fluid drive turbine between the driving shaft and the film driving roller or rollers driven thereby. The turbine drives the roller or rollers at a peripheral speed such that they progressively and smoothly pull the film strip forward. The fluid drive turbine of the invention automatically adjusts its drive to the required film tension.

The fluid drive turbine per se is novel in the disposition of one set of blade sets radially within the other, the use of a different number of blades in one blade set from that in the other, and the configuration and inclination of the blades of the respective sets. All of these features contribute to the smoothness of operation of the fluid drive turbine, and automatic adjustment of the driving torque transmitted therethrough.

The above and further objects and novel features of the invention will more fully appear from the following description when the same is read in connection with the accompanying drawings. It is to be expressly understood, however, that the drawings are for the purpose of illustration only, and are not intended as a definition of the limits of the invention.

BRIEF DESCRIPTION OF THE DRAWING In the drawings, wherein like reference characters refer to like parts throughout the several views,

FIG. 1 is a fragmentary schematic view in plan showing a driving mechanism in accordance with the present invention with a film strip forwarding roller;

FIG. 2 is a view in perspective of the fluid `driving or turbine unit of the mechanism of the invention, the view being taken from the forward end of the fluid driving unit;

FIG. 3 is a view in perspective of such unit showing the other end thereof, the rear end closure plug or plate being removed from the unit;

FIG. 4 is an exploded view in longitudinal axial section through the housing of the fluid driving unit, certain of the parts being shown in elevation;

FIG. 5 is a View in side elevation of the inner, bladed rotor mounted upon the central shaft of the fluid driving unit, a portion of the wall of the hollow shaft facing the reader being broken away;

FIG. 6 is a view in end elevation of the inner, bladed rotor of the fluid driving unit;

FIG. 7 is a view in side elevation of tht bladed outer cage element of the fluid driving unit of the invention;

FIG. 8 is a view in end elevation of the cage of FIG. 7; and

FIG. 9 is a schematic simplified view in end elevation of the inner and outer rotors of the fluid driving mechanisms showing the manner in which they interact with the fluid to provide a yielding drive therethrough.

Turning now to the drawings, in FIG. 1 there is shown somewhat schematically mechanism in accordance with the invention for driving a strip material engaging roller 10. Roller 10 is shown with a film strip 11 passing thereover and travelling upward-ly in FIG. 1. The driving mechanism includes a shaft 12 which is positively driven by means not shown and is journalled in suitable bearings as indicated in FIG. l. Afllxed to the shaft 12 is a sprocket 14 which drives a `drum-like fluid drive unit 16 in accordance with the invention through the medium of a chain 13 which is entrained over the sprocket 14 and a further sprocket 17 which is secured to the housing of unit 16 coaxially thereof. The unit 16 has a hollow output shaft 19 to which is secured a further shaft 18 upon which the film engaging roller is mounted. It will be seen that upon rotation of the shaft 12 in the direction indicated the shaft 18 and the roller 10 are both driven in the direction shown by the arrows so as to forward the film strip 11, as shown.

The construction of the fluid driving unit 16 is shown more particularly in FIGS. 2-5, inclusive. Mounted upon the hollow shaft 19 is an inner, bladed rotor 20 having a sleeve-like radially inner body 21 which has a bore 22 snugly receiving the shaft 19. The rotor is secured to such shaft by a plurality of set screws (two shown) 25 which are threadedly received in radial bores through the body 21, such bores being disposed generally between successive blades. Rotor 20 has a plurality of similar equiangularly spaced blades 24 thereabout, the blades extending longitudinally of the rotor in longitudinal planes disposed at a small angle such as a 10 with respect to the radius of the rotor. In the described embodiment there are 27 blades 24 on the rotor 20.

In order to secure the shaft 18 to the hollow shaft 19 with which it is telescoped, the inner surface of the shaft 19 is provided with a longitudinally extending groove 27 which is adapted to receive a Woodruff key 26 which extends partially within the groove 27 and partially within a further groove (not shown) in the shaft 18. A further set screw 29 is provided in the shaft 19 in order to tighten the shafts 18 and 19 togtther.

The fluid driving unit 16 has a housing or body 30 which is generally in the form of a cup, having a sidewall 31 and an end wall 32. Wall 32 is in the form of a radially inwardly extending flange to the inner edge of which there is integrally attached an axially forwardly extending central hub 34.

The outer blades of the fluid driving device form parts of a turbine blade cage 35 which is retained in the housing 30 by being press fitted thereinto. The blade cage will be further described in connection with FIGS. 7 and 8. There is provided a filler plug 37 having a threaded inner smaller diametered end 39 received in the threaded opening 40 through the sidewall 31 of the housing. The plug 37 has a larger diametered outer end 41 which overlies the paripheral wall of the housing bordering the opening 40 and is sealed thereto.

The axially rear end of the hub 34 of housing 30 is provided with an annular seat 44 which receives therewithin the outer race of an anti-friction bearing 45. A thin spacer washer 46 mounted within a shallow seat in a radially inwardly extending flange 47 forwardly of the seat 44 maintains the inner race of the bearing 45 free from contact with the flange 47. The shaft 19, which is fixedly connected to the inner race of the bearing 45, extends forwardly through the central opening in the flange 47 and through an annular oil seal 50 which is telescoped about the shaft and is fixedly retained in a seat 49 within the forward end of the hub 34.

The construction of the housing and of its bearing and sealing means at the other, rear end of the housing is substantially the same as that at the forward end of the housing with the exception that such latter means are mounted in a removable end plug or plate 51 secured to the rear end of the sidewall 31 of the housing 30. Thus such end of the sidewall of the housing is provided with an internal thread S4 which receives the externally threaded shallow flange 52 on the end plug 51. Plug 51 carries in that order from front to back a bearing, a spacer washer, and an oil seal, all of which are similar to such parts at the righthand end of the housing and are designated by the same reference characters but with an added prime.

The member 35, which carries the outer blades 55 of the fluid driving unit, is in the form of a cage having axially spaced annular end members 56 which are connected by the longitudinally extending outer blades 55. The cage 35, which may be formed, for example, of aluminum, may be made from a tube as by being machined by two key cutters so as to provide the blades S5 with the shape which is more particularly shown in FIG. 8. Each of the blade 55, of which there are provided 28 equally angularly spaced about the cage 3S, has a leading face 57 which lies in a longitudinally disposed plane inclined at an angle with respect to the radial axial plane through the inner end or tip of the lblades 5S. The other, trailing surface 59 of the blades 55 are disposed at an angle with respect to such axial plane. The surfaces 57 and 59 of the blades 55 are formed as above indicated by two milling `cutters of the key cutter type. The first of such cutters, by a series of axial plunge cuts through the peripheral wall of the cage 35, forms the leading surfaces 57 of the blades 55 and the second of such cutters, in a second succession of axial plunge cuts, forms the surfaces 59 of such blades. The angle a may have, for example, a value of 1248, and the angle may have an angle of 10. The cage 35 has an effective inner diameter D Which slightly exceeds the effective diameter d of the inner rotor 20. In a preferred example in accordance with the invention, D has a value of 213511001 and d has a value of 2,115+.002-.000-

As the housing 30 of the fluid driving unit 16 is rotated by the chain 13, the blades 55 of the cage mounted within the housing are rotated and carry with them the fluid suchras oil which substantially fills the space within the housing. Such oil, partially trapped between successive outer blades 55, thrusts upon the blades 24 of the inner rotor and causes the inner rotor to rotate in the same direction as the housing. Such driving effect appears to be produced in two major ways: (l) the oil in the narrow gapbetween the tips of the opposing inner and outer blades because of its viscosity tends to cause the blades of the inner rotor to follow the blades of the outer rotor, and (2) oil is progressively partially trapped in the pockets formed by pairs of inner and outer blades which are substantially in alignment.

In the disclosed embodiment the inner rotor has 27 evenly spaced blades, whereas the outer rotor or cage has 28 equally spaced blades. Thus, as the inner and outer rotors turn slowly with respect to each other, at any one instant some of the pockets formed between confronting sets of blades are virtually closed with the exception of the space between their tips, whereas others of such spacers are markedly open because of the fact that the sets of blades forming such pocket-s are out of alignment to a substantial extent. The effective torque transmitted through the fluid driving mechanism thus remains substantially the same in spite of such slippage. The progressive leakage of fluid under pressure from one pocket of higher pressure t0 another of lower pressure, taken with the progressive shearing of the thin layer or film of oil between the tips of opposing blades, produce the above described very desirable cushioned driving effect of the unit 16.

The fluid employed as the driving medium between the sets of blades in the unit is, as indicated above, preferably an oil. Such oil lubrieates the bearings 45, 45 so that the unit 16 requires little, if any, maintenance. Among the oils which are preferred in a silicone oil designated Dow Corning Fluid #200, which is available in viscosities ranging from to 100,000 centistokes. Such fluid provides outstandingly uniform power transmission characteristics over long periods of use because of its low coefficient of viscosity change with respect to temperature, and its high chemical and physical stability.

By way of example only, a roller shaft such as shaft 18 in FIG. l may have l0 rollers mounted thereon, such rollers being parts of roller trains handling 10 parallel film strips travelling simultaneously through a iilm processing apparatus.

The viscosity in the fluid drive unit 16 driving such shaft 18 with a torque of approximately 9 pound-inches is about 7,000 centistokes. Such torque can be increased by raising the viscosity of the driving uid and decreased by lowering the viscosity of such uid. In practice, all uid drive units which drive successive film strip engaging rollers in an apparatus are usually adjusted to transmit the same torque to each such roller.

Conventional iilm strip developing machines employed in film laboratories process film at an average speed of 150 feet per minute. By way of contrast, tests conducted on similar machines equipped with uid drive units in accordance with the present invention have shown successful operation of such machines at speeds in excess of 400 feet per minute. The improved driving mechanism and the fluid drive unit thereof thus not only provide for the above described improved handling of the lm strip, but elfect marked economies in the processing of the film strip.

There has been thus provided an improved driving mechanism which provides a drive which is characterized by its smoothness, its uniformity, and its automatic control of the driving torque which it delivers. Although not limited thereto, such driving mechanism is advantageous in the driving of means for forwarding film strip, which formerly was conventionally driven by friction driving means which tended to be jerky and uneven in its drive.

Although a limited number of embodiments of the invention have been illustrated in the accompanying drawings and described in the foregoing specificiation, it is to be especially understood that various changes, such as in the relative dimensions of the parts, materials used, and the like, as well as the suggested manner of use of the apparatus of the invention, may be made therein without departing from the spirit and scope of the invention, as will now be apparent to those skilled in the art. Thus although the unit 16 of the invention has been shown as being directly driven by a chain, it is to be understood that, if desired, it may be driven in other manners. One such other manner of driving unit 16 is to dispose it close to and parallel to a driving drum connected to a driven shaft such as shaft 12 herein. One of the members consisting of the drum and the unit 16 is provided with a rubber or rubber-like resilient sleeve which covers its peripheral wall and has frictional driving engagement with the other of such members.

I claim:

1. Driving mechanism comprising a rotatable driven member, a driving shaft and a fluid drive unit interposed between the driving shaft and the driven member for yieldingly driving the driven member, said fluid drive memiber comprising a cylindrical housing, a set of axially disposed evenly spaced, blades of generally saw toothed shape extending inwardly from the inner surface of said housing, said saw toothed blades having leading and trailing face surfaces in respect to the direction of movement of said cylindrical housing, an axially extending sleeve within said cylindrical housing, said sleeve carrying a set of axially disposed outwardly extending evenly spaced blades, said outer and inner blades being formed with opposed confronting end edge faces, said opposed edge faces terminating with a small gap between them, said leading face surfaces of said inwardly extending blades lying in planes being inclined rearwardly at a small angle with respect to radii of the housing passing through thel end faces of said blades.

2. Driving mechanism as in claim 1, said outwardly extending blades lying in planes inclined rearwardly at a small angle with respect to radii of said sleeve passing through the bases of said blades and with respect to the direction of rotation of said sleeve.

3. Driving mechanism as in claim 2, said small angles being substantially the same for said outer and inner blades and being substantially 10.

4. Driving mechanism as in claim 3, said trailing faces of said outer blades also lying in planes inclined rearwardly of a small angle with respect to radii of the housing passing through the end faces of said blades.

References Cited UNITED STATES PATENTS 1,940,918 12/ 1933 Petroni et al 192-58 2,400,186 5/ 1946 Armentrout 192,-58 3,145,892 8/ 1964 Herrmann 226-37 X ALLEN N. KNOWLES, Primary Examiner.

U.S. C1. X.R. 

